|ZUIDERVEEN, GRADY - Michigan State University|
|PADDER, BILAL - Michigan State University|
|KAMFWA, KELVIN - Michigan State University|
|KELLY, JAMES - Michigan State University|
Submitted to: PLOS ONE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/15/2016
Publication Date: 6/6/2016
Citation: Zuiderveen, G.H., Padder, B.A., Kamfwa, K., Song, Q., Kelly, J.D. 2016. Genome-wide association study of anthracnose resistance in Andean beans. PLoS One. 11(6):e0156391.
Interpretive Summary: The common bean is the most important grain legume globally for direct human consumption and is particularly significant in many developing countries. In the tropics and subtropics, bean yields are greatly reduced as beans are susceptible to numerous diseases caused by fungal pathogens. One of the most serious seed-borne diseases and most economically important diseases of common bean is Anthracnose which can cause devastation to farmers’ fields, resulting in yield losses as high as 95% in susceptible cultivars. We utilized a subset of 226 Andean lines to screen against eight races of Anthracnose to identify new sources of resistance, to explore the genetic basis of the resistance, and to identify new genomic regions controlling resistance. In this study, new sources of Anthracnose resistance in Andean beans were discovered on four chromosomes. A major gene for resistance to Anthracnose in both Andean and Mesoamerican beans was identified on chromosome Pv01. In addition, a molecular marker tightly linked to this gene was developed. Information from this study and the marker will be especially useful to scientists at universities, government agencies and companies who want to breed better beans.
Technical Abstract: Anthracnose is a seed-borne disease of common bean (Phaseolus vulgaris L.) caused by the fungus Colletotrichum lindemuthianum, and the pathogen is cosmopolitan in distribution. The objectives of this study were to identify new sources of anthracnose resistance in a diverse panel of 230 Andean beans comprised of multiple seed types and market classes from the Americas, Africa, and Europe, and explore the genetic basis of this resistance using genome-wide association mapping analysis (GWAS). Twenty-eight of the 230 lines tested were resistant to six out of the eight races screened, but only one cultivar Uyole98 was resistant to all eight races (7, 39, 55, 65, 73, 109, 2047, and 3481) included in the study. Outputs from the GWAS indicated major quantitative trait loci (QTL) for resistance on three chromosomes, Pv01, Pv02, and Pv04 and two minor QTL were detected on Pv10 and Pv11. Candidate genes associated with the significant SNPs were detected on all five chromosomes. An independent QTL study was conducted to confirm the physical location of the Co-1 locus identified on Pv01 in an F4:6 recombinant inbred line (RIL) population. Resistance was determined to be conditioned by the single dominant gene Co-1 that mapped between 50.16 and 50.30 Mb on Pv01 and an InDel marker (NDSU_IND_1_50.2219) tightly linked to the gene was developed. The information reported will provide breeders with new and diverse sources of resistance and genomic regions to target in the development of anthracnose resistance in Andean beans.